'It was time for me to show myself, and the world, that my success was not an accident.'

Designer Diane von Furstenberg was 27 when she made the first wrap dress in 1974. The iconic design landed her on the cover of Newsweek — and millions of women snapped up her dresses. But when demand faded, von Furstenberg ended up selling most of her licenses to avoid bankruptcy. In 1997, von Furstenberg relaunched her company, which now has annual sales of more than $200 million. The wrap dress, too, made a comeback, and recently celebrated its 40th anniversary with "The Journey of the Dress" exhibition, which traveled the globe. And, as the 68-year-old designer recently shared with Inc. contributing editor Liz Welch, she is focused on building a company to outlast any fad.

My business career has been divided into three phases, starting with the "American dream" phase. I was in my 20s when I came to America from Europe, and I made this dress that tapped into the Zeitgeist. It was sexy but effortless. Easy and functional. It was empowering just as women were beginning to feel empowered. That was a once-in-a-lifetime thing.

In 1997, I decided to relaunch my brand using that dress. Fashion had changed by then, but I saw all these young hip girls buying that dress in vintage shops. I call that stage "the comeback years." It was time for me to show myself, and the world, that my success was not an accident. But I ran into trouble. We started to grow, I brought in a creative director, we tried to do too many things, and we lost our reason for being. I had to find that again. This is what you must do time and again as an entrepreneur.

I've learned to rely on my instinct, impulse, and passion. This is what entrepreneurs do best. It's what makes your company unique — the heart of your business, the engine. You also need a solid business plan and a great team — but the important thing is to not lose yourself.

I've come to realize that when you have your first success, it is often the essence of who you are and what you do. Trust that. Because as you grow and become more successful and hire more people, you can forget what you stood for in the first place. You have to stay true to yourself. That way, even if you make mistakes, it's OK, because you stand for it.

Last year, I started a new phase that I'm calling "legacy." That's when you realize that you have built something significant enough that it will last. But it also means building the next level of infrastructure to compete with the huge global brands. And at each moment, each phase of the business, you encounter new challenges equally as complicated but totally different, depending on the phase.

For me, I returned to the dress and realized that it was more than a dress. I had to extract why it hit, what was the Zeitgeist, what did the dress stand for? That's the spirit of the brand. That's long lasting. That can live forever.

It was only this year, when I created the exhibition, that I truly saw the power of that dress. I realized not only what it did for me but what it did for so many people. Now, I have to make sure that I have carved into our DNA all the things that the dress stands for: empowerment, sexiness, effortlessness.

Ben Eine, a graffiti-vandal-turned-popular-street-artist, stood at the foot of a massive stone wall Monday evening, smoking a cigarette with paint-covered hands. He was in a parking lot at Wabash Avenue and Harrison Street, where the "L" tracks bend snake-like as the Orange Line rattles in and...